I ended up putting in a DiMarzio Area 67, simply because that what is also in the Charvel Henrik Danhage, which is also an HS with no tone knob.
I need to dial down the volume a little when using it otherwise it has a bit too much treble, but it mostly works for scratching the itch. Definitely tempted to try out others though.
The neck pickup that came with the Frankie was a bit too noisy when I tried it, though I also didn't have the noise gate dialed in with my main preset, so maybe it isn't too bad.
I ended up putting it in the existing lower tone knob hole, though I'm not super happy with the location since it is a little out of the way (and the bar can be in the way).
Seems like putting it in front of the volume knob might be better location.
I also installed a 3-way pickup selector, though I never use the middle, so maybe a toggle would have been better. I briefly investigated tracking down a low friction push-push/push-pull, but decided to just not mess with the volume knob.
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